Ibn Rajab reports that classical Arab doctors used to say:
الْحَمِيَّةُ رَأْسُ الدَّوَاءِ وَالْبِطْنَةُ رَأْسُ الدَّاءِ
Diet is the foundation of medicine and the stomach is the foundation of illness.
Source: Jāmi’ al-‘Ulūm wal-Ḥikam 2/468
Praise be to Allaah. There is no doubt that what you have done is a kind of zinaa (unlawful sexual activity), although it is not the worst kind, so you must repent sincerely to Allaah, give up this sin, regret what has happened and be determined never to go back to it. Avoid bad friends and bad places, lower your gaze and keep your distance from women to whom you are not related (non-mahram). If you repent to Allaah, He will accept your repentance. You are still a Muslim, but you have committed an act of disobedience towards Allaah by doing this sinful act, so come back to your Lord and seek His forgiveness for what you have done. Do more good deeds to expiate for and cancel out your bad deeds, do those things that will help you to remain chaste, and hasten to marry according to Islam. Finally, we will leave you with a story from which you may learn a valuable lesson: Ibn Mas’ood reported that a man came to the Prophet (peace and blessings of Allaah be upon him) and told him that h...